A mathematical model of heat and mass transfer in the system «vertical well-oil pool» system is constructed. Method of interpreting the results of thermo-hydrodynamic studies of vertical oil wells on the basis of the theory of ill-posed problems is developed. The results of calculations real on the welltest data are presented.

The shunt for pulse current measurement which resistive section made as corrugated tube is proposed. In the first place, it permits the shunt’s length extending without inductivity increasing at the same time. In the second place, the corrugation increases the tube strength and allows minimization of walls thickness. This results in decrease of the transient response rise time (expanding of passband). The shunt can be used for measurement of heavy current with amplitude up to 200 kA.

The methods of error calculation under determination of electronic components impedance by S -parameters measurements results carried out by means of vector analyzer of circuitry are considered. The expressions connecting the impedance measurement error the measuring instrument effective parameters are obtained. The typical calculation by the example of precision vector analyzer of circuitry S5048.